(a) Field of the invention:
The present invention relates to a formation and making method of an integrated light-triggered and light-quenched static induction thyristor (hereinafter abbreviated as LTQSI thyristor) composed by integrating a light-triggered static induction thyristor (hereinafter abbreviated as LTSI thyristor) and static induction phototransistors (hereinafter abbreviated as SIPTs) or a photodarlington circuit including a light-triggered static induction thyristor and static induction phototransistors.
(b) Description of the prior art:
Formational examples of LTQSI thyristors have already been proposed by Japanese Patent Preliminary Publication Nos. Sho 60-198779 and Sho 61-54668 whereas and a making method thereof has been disclosed by Japanese Patent Preliminary Publication No. Sho 62-11470. The LTQSI thyristors proposed by these patents, however, have a drawback that the SIPT thereof has a current gain level lower than that obtainable by the SIPT operated in the normal mode since the former is operated in the inverse mod when quenched by light.